I'm 99% sure I've found the solution to prevent all the crashes that happen on linux.
For two days the client crashed regularly. After my fix not a single crash or database corruption in 8 hours!!
The crash and database damage happen only if the client is run more than once at the same time.
Now you may ask, why run the client a second time?
A lot of people do it, to read the status from the client, meaning ...
a script starts bitcoind --daemon
but then either another script, cron, or manual command line is used in this way:
watch 'bitcoind getmininginfo & bitcoind listaccounts'
and this watch command calls bitcoind every two seconds, and there is a small chance that the daemon will crash. or it's caused by a memory leak, but not by the deamon, but by the getmininginfo call performed every 2 seconds!
I've disabled my watch script on all 5 linux instances, did no other chances whatsoever (besides a reset to make sure the damage done by watch/getmininginfo is gone), and after 2 days full of crashes, not a single memorycoin daemon crash, in over 8 hours of mining!
I hope this helps.